Static Analysis for the No Termination Problem in Active Databases by Using Petri Nets Modelling

Abstract

∗Traditionally, databases are introduced to store information as a repository of data; however, users are responsible to add, remove, and modify database records. In order to provide reactiveness to passive database systems, the concept of active database was introduced. Active behavior can be denoted via Event-Condition-Action (ECA) rules. Nevertheless, ECA-rules may concatenate, producing loops in the rule’s firing and, in consequence, inconsistent states in the database system. This situation is known as the No-Termination problem. In this paper, a recursive algorithm based on Petri Nets to detect the No-Termination problem is proposed. The algorithm takes into account a Petri Net representation for ECA rules and composite events. Furthermore, an execution time analysis of the algorithm is carried out for sets of ECA rules with several cycles.